You just got it or just built it? Big difference here because if you just got it and you open the case you may void your warranty! Please read your warranty manual before opening it up.
Try this:
go to control panel and power options and change the power schemes to always on and then adjust your adjust monitor time to about 20 minutes. Then in the same area the hibernate tab and uncheck the hibernate box.
let us know if it helps or not

maybe its some unstable things going on. i dunno if it has to do with power schemes... please go into more detail though. ur playing it... and it just crashes? the whole computer just shuts down and the screen into hibernate?

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Macbook Pro and Logitech z5500s. All you really need.

Yeah, your RAM could be the problem, but if it hasn't been built properly, it could be temperature issues too, or your video card.

I'd take it back, and get them to repair or replace it since its new Or did you build it yourself? If you did, I'd presume the video card to be more the fault than the RAM.

One thing though, there shouldn't be an issue with the graphics card, since BFG auto overclocks the cards anyways to work better, but it could still be the card if somethings not working right. But it could also be the RAM, though this seems less apparent.

I hope this helps

EDIT: Does anyone know if Geforce cards have a VPU recover like ATi cards do that can be switched on to see if it recovers from a crash?